1. Field of the Invention
The present invention relates to a picking system and a picking method.
2. Description of the Related Art
When picking commodities, piece by piece, from so many various types of commodities in response to requests by customers, operators walk around with a cart in a warehouse to pick the commodities from the racks in accordance with the display on a screen of the cart. In this case, the operators must walk a long distance from one rack including a commodity to another rack including another commodity.
A picking system is known, where rail-guided vehicles are combined with an automated storage and retrieval warehouse including stacker cranes and racks, and containers containing commodities are transported to a picking area by the rail-guided vehicles. Further, conveyors connecting the picking area and a shipment area are also known. In this case, since the system may deal with very many types of commodities, very many racks are needed, and thus, many lanes for the many stacker cranes and many rail-guided vehicles are required. Furthermore, because a stacker crane can only reciprocate within a single lane, a plurality of stacker cranes are needed to pick commodities for one shipping destination.
JP S63-242809A proposes transporting articles by overhead travelling vehicles between an arrival area of a factory, a plurality of racks in a component warehouse, and assembly lines. Furthermore, according to JP S63-242809A, the travelling route for the overhead travelling vehicles is provided with a diverging section and a merging section so that the overhead travelling vehicles may access the plurality of racks. However, JP S63-242809A does not consider picking.